In recent years noise pollution has been recognized as being a primary causation of neurosis. Everyone is associated with many environments which are unduly noisy; however, those who are forced to continuously live in noisy environments are not always aware of the excessive background noise. Moreover, many people are forced to share a common environment, and invariably a few of these people habitually make obnoxious or excessive noises which are repugnant to their fellow man. For example, a person may snore in his sleep and never realize that this obnoxious habit is the prime reason for his roommate's neurotic behvaior. Librarians find it tiresome to continually remind noisy people of the necessity for quietness in the study room. Public school class rooms are not always as tranquil as the instructor might desire.
Apparatus which sequentially listens for and detects a predetermined noise level that lasts for a predetermined length of time, and thereafter sounds an alarm in a cyclical manner when the magnitude of the noise reaches a set level of sound and duration is the subject of the present invention. The alarm ceases when the noise level decreases below the preset level.